Menu Close

If-and-are-roots-of-the-equation-x-3-px-q-0-p-0-q-0-then-find-the-value-of-the-determinant-determinant-




Question Number 363 by rajabhay last updated on 25/Jan/15
If α, β and γ are roots of the equation  x^3 +px+q=0, p≠0, q≠0 then find the  value of the determinant.   determinant ((α,β,γ),(β,γ,α),(γ,α,β))
Ifα,βandγarerootsoftheequationx3+px+q=0,p0,q0thenfindthevalueofthedeterminant.|αβγβγαγαβ|
Commented by 123456 last updated on 24/Dec/14
 determinant ((α,β,γ),(β,γ,α),(γ,α,β))=3αβγ−(α^3 +β^3 +γ^3 )  x^3 +px+q=0  α+β+γ=0  αβ+αγ+βγ=p  αβγ=−q
|αβγβγαγαβ|=3αβγ(α3+β3+γ3)x3+px+q=0α+β+γ=0αβ+αγ+βγ=pαβγ=q
Answered by prakash jain last updated on 24/Dec/14
 determinant ((α,β,γ),(β,γ,α),(γ,α,β))= determinant (((α+β+γ),β,γ),((β+γ+α),γ,α),((γ+α+β),α,β))  (C_1 =C_1 +C_2 +C_3 )  = determinant ((0,β,γ),(0,γ,α),(0,α,β))=0
|αβγβγαγαβ|=|α+β+γβγβ+γ+αγαγ+α+βαβ|(C1=C1+C2+C3)=|0βγ0γα0αβ|=0